Prior art comminuting apparatus for reducing large diameter wood products and stumps to a desired size, have comprised a reduction chamber, with an impact rotor positioned concentrically therein, in combination with a housing, drive motor and infeed chute. The impact rotor is formed with a plurality of horizontally elongated impact strikers at its periphery. The rotor is positioned so that the elongated wood product or stump falling under the influence of gravity through the infeed chute is directed against the strikers, and repelled ahead of the rotor's rotational direction against an anvil formed along one side of the reduction chamber.
In prior art, wood comminuting apparatus, is often capable of comminuting trees or parts thereof up to 40 inches in diameter (see e.g. U.S. Pat. No. 5,165,611), strikers used for the comminution are bolted directly to mounting projections on the rotor which is rotated to produce the comminution. Maintenance to change strikers has required complete removal of the striker mounting bolts with a consequent potential loss of bolts and uneconomical use of maintenance time, especially in view of the substantial number of strikers on a rotor of such apparatus. Also the strikers of the prior art are only as wide as segments of the rotor with the result that wear on outer edges of the cutting edges of the strikers leaves gaps in cutting edges between segments leading to inefficient comminution and shortened striker life.